We investigate the multipath characteristics of the impulse radios (IR) which have drawn much attention for future high-speed wireless communication services. For this objective, we observe the characteristics of bit error rates through computer simulations for the deterministic two-path model and the statistical indoor multipath model of Saleh and Valenzuela (1987). The simulation results indicate that the performance of the IR system depends on the time-delay differences between the multipath components, the path gains, the time interval in the PPM, and the reference signal waveform. It is also observed that the reference signal waveform used in the AWGN channel can not be applicable to the multipath channel.